The invention came too late to use in a telescope. The purity came from the raw materials reacting to make silicon tetrachloride, which evaporated at 58 ☌, leaving all the impurities behind. Franklin Hyde, squirted liquid silicon tetrachloride into an oxy-hydrogen flame to yield a powdery white “soot” that was pure SiO 2. Pure silica had even lower thermal expansion, but no process existed to make it in quantity until a young chemist, J. The company had used a borosilicate glass, Pyrex, to cast the 200-inch Palomar mirror in the early 1930s. Ĭorning also had already developed fused silica for applications that took advantage of its low thermal expansion. One is you may succeed where they fail, of course, but even if you fail you will gather information that they don’t gather,” he said in a 1995 interview.įrank Hyde at work in his lab circa 1934. “If you do something that is different from what everybody else is doing, you’ve got two advantages. “I had no reason to think it was any better, but nobody else was working on it.” His strategy was deliberately contrarian. “That was one of the reasons I started with silica,” says Maurer. Starting with optical glass seemed the obvious choice plenty of glass compositions were available for use as core and cladding, as were ovens for melting it. “Most talk was how to purify the raw materials used to make meltable glasses,” recalls Maurer. There were two possible starting points: well-developed optical glasses that required extensive purification or fused silica (SiO 2), which was extremely pure but had to be melted at very high temperatures and had such a low refractive index that the fiber core would have to be alloyed with a high-index material.įiber communication’s main challenges were making glass so pure it absorbed very little light, and drawing it into light-guiding fibers with a high-index core and lower-index cladding. Seeking the purest glassįiber communication’s two main challenges were making glass so pure it absorbed or scattered very little light, and drawing it into light-guiding fibers with a high-index core and a lower-index cladding. His results in the December 1956 Journal of Chemical Physics initially were controversial, but they proved correct, and Kao cited them in his own 1966 landmark paper. Maurer showed that light scattering varied little with angle, supporting the frozen-liquid theory. Yet many measurements showed 10 to 100 times more scattering than expected. Theory considered glass as a liquid with atoms frozen in random positions, uniform except for small, random microstructures. in low-temperature physics from the Massachusetts Institute of Technology, USA, and became a glass expert by doing fundamental research on the nature of glass. Maurer had joined Corning in 1952 with a Ph.D. “There was no great urgency,” recalls Maurer. Research director Bill Armistead liked the idea, but assigned it to the fundamental-physics research group that Maurer headed. That would require reducing loss by 980 dB/km-a forbiddingly large factor of 10 98. Kao’s plan needed fibers with losses of 20 decibels per kilometer, to carry signals roughly 10 km. Ĭorning already made bundled fiber optics for medical and military use, but the light paths were no longer than a couple of meters, with losses of a decibel per meter. Peter Schultz (left), Donald Keck and Robert Maurer pose at Corning with the first optical cable made for communications, under a contract from the Naval Electronics Command in San Diego, CA, USA.
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